1. Field of the Invention
The present invention relates to a display device for displaying an image.
2. Description of the Related Art
As a display device, for example, there is known a head-up display (HUD) device which is disposed inside of a vehicle and which is designed to project an image displayed on a display unit on a front window (e.g. Japanese Patent Application Laid-open Nos. 2007-65011 and 2011-53386).
Technologies disclosed in Japanese Patent Application Laid-open Nos. 2007-65011 and 2011-53386 are for displaying a virtual image approximately vertically on a road surface. Recently, however, efforts have been made for displaying a virtual image on a road surface by means of a vehicle-mounted head-up display device. In order to display a virtual image approximately vertically on a road surface, it is enough to dispose a display device such as a liquid crystal display device approximately vertically to the road surface. In order to display a virtual image on a road surface, instead, those skilled in the art may consider inclining a display surface of a display device toward the road surface, for example. In this case, depending on the viewing angle of the display device, the virtual image may be displayed insufficiently, or the transmittance and contrast of the display panel may decrease. Japanese Patent Application Laid-open Nos. 2007-65011 and 2011-53386 does not disclose or suggest displaying any virtual image on a road surface. There is a need for a display device for displaying a virtual image on a road surface.